Support TOML markup

[schaefi]

Allow to use TOML markup for the kiwi image description This Fixes #2372

[schaefi]

To convert your image description to TOML call

kiwi-ng image info --description path/to/description --print-toml

Take the output and place it into a file that has to end with .kiwi Description files with this extension goes through anymarkup on reading and will be parsed in their markup

[schaefi]

I did not add support for TOML so far because it adds a new python module requirement as you know.
I don't think this change here is backward compatible, but supporting more markups is easy :)

[schaefi]

@Conan-Kudo I haven't heard back from the anymarkup people and guess they are not interested. I would continue adding the toml support but implement it as a plugin such that we don't create a hard requirement to the toml module. Thoughts ?

[Conan-Kudo]

I'm concerned that anymarkup might be abandoned. If that's the case, we're going to have to take ownership of that module.

[schaefi]

I'm concerned that anymarkup might be abandoned. If that's the case, we're going to have to take ownership of that module.

It's a different question. From my perspective it's not an orphan module but there is not much development happening anymore and it just does it's job in a good way. If need be we can certainly take ownership. From today's perspective and dev power in the kiwi team I would say it will not get more attention that it gets now ;)

Brings me back to the question if we should support the TOML markup in plugin style to prevent kiwi from another requirement or if we should not add TOML markup support at all ? I don't have any pressing requests for TOML but as we have YAML and coding that as a plugin is easy why not do it ?

[Conan-Kudo]

Let's ship it as-is. Even the toml module's dead state isn't that big of a deal right now.